Durable press finish for wool/cellulosic fabrics (melamine/uron resins)

ABSTRACT

A method for imparting durable press properties to textile fabrics containing wool and cellulose, comprising impregnating the fabric with a methylated trimethylol melamine, bis(methoxymethyl)uron, a member selected from the group consisting of pentamethylol melamine and hexamethylol melamine, and a delayed action catalyst, and subsequently curing said melamines on said fabric, the composition for the method and the treated textile.

United States Patent Roth [54] DURABLE PRESS FINISH FOR WOOL/CELLULOSIC FABRICS (MELAMINE/URON RESINS) [72] Inventor: Philip B. Roth, Bridgewater Township,

Somerset County, Somerville, NJ.

[73] Assignee: Koratron Company, Incorporated, San

Francisco, Calif.

22 Filed: July 29,1968

211 Appl.No.: 748,175

52 us. c1 ..117/1o,117/11,117/139.4, 4 .1.. 7, ,1.4, A, 17/ 4 .,2/243313/ 1 4 51 int. c1.....

[58] Field ofSearch ..1l7/139.4,143 R, 145, 141, 117/1395 R, 10, 11; 260/849; 8/1162, 116.4, 128

[ 5] Feb.1,1972

[56] References Cited UNITED STATES PATENTS 2,974,432 3/1961 Warnock et a1 ..1 17/1394 X 3,063,869 11/1962 Roth ..ll7/l39.4

Primary ExaminerWilliam D. Martin Assistant Examiner-Theodore G. Davis Attorney-Charles J. Fickey [57] ABSTRACT 13 Claims, No Drawings DURABLE PRESS FINISH FOR WOOL/CELLULOSIC FABRICS (MELAMINE/URON RESlNS) This invention relates to durable press finishes. More particularly, it relates to a method for imparting durable press properties to textile materials containing wool and cellulosic fibers by applying an aqueous solution of methylol melamine and methylol uron resins" and curing the resins on the textile material. It more particularly relates to such a method using a deferred curing operation. It also relates to the textile material thus treated.

Durable press finishes for cellulosic textile materials, particularly for blends of cellulosic fibers with synthetic fibers such as Dacron and nylon, are well known. The deferred curing technology of such finishes is also well known. Large amounts of fabric are treated with the finishes and dried. Manufacturers then cut and sew the fabric into garments, and the garments are pressed to impart creases where creases are desired and smoothness and shape where creases are not desired. Finished garments are then heated in an oven, or otherwise, to affect the curing of the finish on the completed garments. The Koret patent, US. Pat. No. 2,974,432, describes the above process, now known as the Koratron process.

The preferred finish for use in the Koratron process contains 4,5-dihydroxy-l,3-dimethylol-2-imidazolidinone, commonly called dimethylol-dihydroxy-ethyleneurea. A curing catalyst, such as zinc nitrate, is also normally present in the finish. The finish, when applied by a deferred cure process, imparts excellent durable press properties to cellulosic, and blends of cellulosic and synthetic, textile materials.

Satisfactory durable press properties are not obtained when the above finish is applied by the deferred curing method to blends of wool and cellulosic fibers. Although good durable press properties can be imparted by applying two textile finishes in separate operations to blends of wool and cellulosic fibers, such operations are obviously time-consuming and undesirable.

The object of this invention is to provide a single bath durable press finish for textile materials containing wool and cellulosic fibers, Le, a finish suitable for the deferred. curing method. Also, the finish should not only provide crease retention where creases are desired and smoothness of fabric where creases and wrinkles are not desired, but these qualities must persist after laundering. Furthermore, the finish should provide resistance to shrinkage due to laundering, and the hand of the fiber should be satisfactory. Lastly, the treated and dried fabric must be stable to storage before curing.

It has now been discovered that the above objects can be attained by (l) applying an aqueous solution containing two types of aminoplast resins to a textile fabric containing wool and cellulosic fibers, (2) drying the treated fabric at a temperature below the curing temperature, and (3) subjecting the dried fabric to a curing operation, either conventional or deferred.

Fabric to be treated by the process of this invention contains at least 40 percent, preferably at least 45 percent, of wool fibers and at least percent, preferably at least percent, of cellulosic fibers. Cellulosic fibers include cotton and regenerated cellulose, i.e., rayon, particularly viscose rayon. Other fibers may be present, including the synthetic fibers such as the polyamide (nylon) fibers, polyester (Dacron) fibers and polyacrylic (Orlon and Creslan) fibers.

The two types of aminoplast resins or reactants (i.e., the resin or reactant precondensate) are l) bis(methoxymethyl)uron and (2) a combination of melamine resins. The melamine resins must include methylated trimethylol melamine and either of methylated pentaor hexamethylolmelamine or both the pentaand hexamethylolmelarnine. By trimethylolmelamine, it will be understood that the average number of methylol groups is from about 2.8 to 3.2. The number of methylol groups which are methylated is about 50 percent. Both types of aminoplasts are well known and find extensive use on cellulosic fibers. The methylol melamines also find use on wool to reduce shrinkage and felting.

The two types of aminoplast resins are compatible in aqueous solution. The wool/cellulosic fabric is impregnated with the resin solution by any of the well-known procedures, including dipping, padding, spraying, etc.

The amount of trimethylolmelamine-based resin applied on the fabric is between 3 and 25 percent on the weight of the fabric (o.w.f.), preferably between 4 and 18 percent o.w.f. The amount of uron-based resin applied is between 2 and 18 percent o.w.f., preferably between 3.5 and 12 percent o.w.f. The amount of melamine resin with five to six methylol groups is from 5 to percent, preferably from about 5 to 25 percent, based on the amount of uron resin. The total aminoplast resin should be at least 7 percent o.w.f., preferably at least 20 percent o.w.f.

Since the treated wool/cellulosic fabrics will normally pick up between 70 and percent of their weight of treating solution, the amount of melamine-based resin in the solution will be between 4 and 20 percent of the solution, preferably between 6 and 15 percent. The amount of uron-based resin will be between 3 and 15 percent, preferably between 5 and 10 percent.

A curing catalyst of the delayed action type should also be applied to the fabric. This can be done conveniently by dissolving the catalyst in the resin solution. The catalyst utilized may be free acid, acid salt, alkanolamine salt, metal salt, and the like. The concentration of catalyst employed may range from about 0.1 to 25 percent or higher, based on the weight of the resin solids, depending upon the particular catalyst type employed. Thus, for example, from between about 0.1 and about 10 percent of a free acid, such as phosphoric, tartaric, oxalic or the like, may be employed, while in the case of ammoniurn chloride, amounts of from between 0.5 and about 10 percent are used. In the case of amine salt, including alkanolamine salts, such as diethanolamine hydrochloride, from about 1.0 to about 10 percent are most useful, while with respect to salts such as magnesium chloride, zinc chloride, zinc nitrate, and aluminum chloride, amounts of between about 5 and 25 percent, preferably 8 to 15 percent, have been successfully employed. in all instances, the concentration of the catalyst is based on the weight of the resin solids employed.

After impregnation with the resin and catalyst solution, the fabric is dried at a temperature below 2.50" F., preferably at a temperature between 200 and 230 F. At the preferred range, between 1 and 10 minutes will normally be required.

Although the treated and dried fabric can be cured immediately, or after storage, in the flat state, full benefit of this invention is obtained by cutting and sewing the treated, dried fabric into garments, which are pressed and shaped as desired. The garments are then heated, as in an oven, for a sufficient length of time to effect a cure of the resin finish on the fabric of the garment. The garment thus acquires a durable press, with shape, desired creases and smoothness of the fabric, where each is desired.

The recommended curing temperature is between 290 and 350 F., preferably between 300 and 340 F. Curing time will range from about 41 to 30 minutes depending on the temperature used.

if desired, other textile treating agents and additives may be present in the resin/catalyst impregnating solution. These additives include softeners, water repellents, surface active agents, etc.

In the following examples, the percentages are by weight. The retention of creases was evaluated by the AATCC Tentative Test Method 88C-l964T. The smoothness of the fabric, i.e., the minimum care appearance, was evaluated by AATCC Tentative Test Method 88-A-l964T, employing overhead lighting. The fabrics were rated on a scale of 1-5, 5 representing the smoothest appearance and best retention of the original condition and 1" representing the poorest appearance and poorest retention of the original condition.

The examples are given to illustrate the invention and are not intended to be limitative.

EXAMPLE 1 A 50/50 wool/rayon fabric was immersed in an aqueous solution containing 1 1.3 percent of partially methylated trimethylolmelamine (Resin A), 1.6 percent of hexa(methoxymethyl)melamine (Resin B), 6.0 percent of bis(methoxymethyl)uron (Resin C), 1.8 percent of zinc nitrate (Catalyst A), 1.1 percent of stearoylethyl dihydroxypropyl dimethyl ammonium chloride (Softener A), and 0.25 percent of ethylene oxide adduct of nonylphenol (Surfactant A). The fabric was then passed through suitable rolls, as in a padder, so that the fabric had a 95 percent wet pickup. The fabric was dried at 210 F. for 5 minutes. The treated fabric contained 12.2 percent of melamine resin and 5.7 percent of uron resin.

A portion of the dried fabric was pressed to impart a crease and then cured by heating in an oven at 315 F. for minutes. The cured fabric was washed in a home-style, automatic washing machine using water at 140F. and a detergent. The washed fabric was tumble dried.

The shrinkage of the pressed and cured fabric was measured before and after five washing cycles. The shrinkage of the untreated fabric was also measured. The results are shown in table 1 as the percent shrinkage of warp (W) and fill (F).

TABLE 1 The cured fabric exhibited excellent crease retention and excellent minimum care appearance after the washings.

A portion of the dried, but uncured, fabric was stored for 7 weeks. Samples of this fabric were pressed to form a crease and cured at 315 F. for 10 minutes, 350 F. for 10 and 20 minutes, and 360 F. for 10 and 20 minutes. All samples after washing 5 times as described above exhibited excellent crease retention and excellent (5 rating) minimum care appearance.

The example demonstrates the effectiveness of the finish of this invention in imparting shrinkage resistance, permanent press and minimum care properties, after a postcuring operation, to a wool/rayon fabric. The stability to storage of the dried fabric before pressing and curing is also shown.

EXAMPLE 2 Three pad baths are prepared of the following composition:

The pad baths were applied to 50/40/10 wool/rayon/nylon fabric by a standard padding procedure obtaining wet pickup of 80 percent. The fabrics were dried at 225 F. for 4 minutes. The fabrics contained 10.3 percent, 7.7 percent and 6.1 percent of melamine resin and 4.8 percent of uron resin.

Swatches of the dried fabric were creased by pressing for 10 seconds at 310 F. The swatches were then heated in an oven at 340 F. for 10 minutes. The swatches were washed five times in a home-style washing machine using water at 140 F., tumble drying after each washing cycle.

The shrinkage of the washed fabrics, including a swatch of washed untreated fabric, is shown in table 111 as percent shrinkage of warp and fill. Crease retention and minimum care appearance of the washed fabrics are also shown in the table. Fabrics l, 2 and 3 correspond with pad baths 1, 2 and 3, respectively.

TABLE 111 Shrinkage Crease Minimum Care Fabric W F Retention Appearance Untreated 10.0 8.0

1 2.0 3.3 Excellent 5 2 2.0 3.6 v Excellent 5 3 3.0 4.6 Fair 4 EXAMPLE 3 A 50/50 wool/rayon fabric was immersed in an aqueous solution containing 10.0 percent of Resin A, 0.94 percent of Resin B, 5.3 percent of Resin C, 0.4 percent of mixed siloxanes (Water Repellent A) and 1.9 percent of magnesium chloride (Catalyst B). The fabric was squeezed through rollers to impart a percent wet pickup and the fabric was dried at 225 F. for 3.5 minutes. The fabric contained 10.4 percent melamine resin and 5.0 percent of uron resin.

Swatches of the dried fabrics were creased by pressing at 310 F. for 15 seconds, (1) immediately after drying, (2) after 14 days at F and (3) after 7 weeks at room temperature.

All of the fabrics demonstrated excellent crease retention after 5 washings in an automatic washing machine using water at 120 F.

EXAMPLE 4 Two pad baths were prepared of the following composition:

' Zinc palmitate The pad baths were applied to 50/50 wool/rayon fabric by a standard padding procedure obtaining a wet pickup of 80 percent. The fabrics were dried at 225 F. The fabrics contained 5.7 and 6.5 percent of melamine resin and 4.25 and 8.5 percent of uron resins, respectively.

Swatches of the fabrics were creased by pressing at 350 F. for 15 minutes. The pressed swatches were then heated in an oven at 310 F. for 10 minutes. i

The shrinkage of the untreated and treated and cured fabrics was determined after washing for 5 times in an automatic washing machine with water at 120 F. Fabrics 1 and 2 correspond to pad baths 1 and 2, respectively. The crease resistance and minimum care appearance of the pressed fabric after washing are shown in table V.

Three pad baths were prepared of the following compositions:

Pad Bath 1 Par! Bath 2 Pad Bath 3 Resin A 10.0% 10.0% 10.0% Resin B 0.94 0.94 0.94 Resin C 5.3 5.3 5.3

Water repellent A 1.25 [.25 1.25 Surfactant B' 0.1 0.l 0.l

Catalyst A 1.6 Catalyst 8 1.9 Catalyst C 0.7.3 0.23 0.23 Catalyst D" L Condensate of nonphcnol and about 9 moles ol'ethylene oxide.

"' Mixed isopropylamine hydrochlorides.

TABLE V Crease Minimum Care Fabric Retention Appearance 1 Excellent 2 Excellent 5 3 Excellent 5 While 1 have set forth certain specific examples and preferred modes of practice of my invention, it will be understood that this is solely for purposes of illustration and that various changes and modifications may be made without departing from the spirit of the disclosure or the scope of the appended claims.

lclaim:

1. A method for imparting durable press properties to textile fabrics containing wool and cellulose, comprising impregnating the fabric with an aqueous medium containing a methylated trimethylol melamine bis(m-ethoxyrnethyl) uron, a member selected from the group consisting of pentamethylol melamine and hexamethylol melamine, and a delayed action catalyst, said trimethylol melamine being from about 3 to 25 percent and said uron being from about 2 to about 18 percent based on the weight of said fabric and said member selected from the group consisting of pentamethylol melamine and hexamethylol melamine being from about 5 to about percent based on the weight of said uron, and subsequently drying and curing said impregnated fabric.

2. The method of claim 1 wherein said catalyst is a zinc salt.

3. The method of claim 1 wherein said catalyst is zinc nitrate.

4. The method of claim 1 wherein said melamines and uron are applied in a combined weight from about 7 to 40 percent on the weight of fabric.

5. The method of claim 1 wherein said textile fabric con- I tains at least 40 percent wool and at least 20 percent cellulose.

6. The method of claim 1 wherein said textile fabric contains synthetic fibers.

7. A textile material having crease resistance properties as produced by the method of claim 1.

8. The method of claim 1 wherein, subsequent to said drying, said fabric is formed into garments, creases are imparted to portions of said garments, and said curing step is then applied.

9. The method of claim 1 in which said trimethylol melamine is about 4 to about 18 percent, said uron is about 3.5 to about 12 percent, and said member about 5 to about 25 percent.

10. The method of claim 1 in which said impregnated fabric is cured at a temperature of about 290 to about 350 F. for

about A to about 30 minutes.

11. The method of claim 5 in which said textile fabric contains synthetic fibers.

12. A permanently creased garment as produced by the method of claim 8.

13. The method of claim 8 in which said impregnated fabric is cured at a temperature of about 290 to about 350 F. for about A to about 30 minutes. 

2. The method of claim 1 wherein said catalyst is a zinc salt.
 3. The method of claim 1 wherein said catalyst is zinc nitrate.
 4. The method of claim 1 wherein said melamines and uron are applied in a combined weight from about 7 to 40 percent on the weight of fabric.
 5. The method of claim 1 wherein said textile fabric contains at least 40 percent wool and at least 20 percent cellulose.
 6. The method of claim 1 wherein said textile fabric contains synthetic fibers.
 7. A textile material having crease resistance properties as produced by the method of claim
 1. 8. The method of claim 1 wherein, subsequent to said drying, said fabric is formed into garments, creases are imparted to portions of said garments, and said curing step is then applied.
 9. The method of claim 1 in which said trimethylol melamine is about 4 to about 18 percent, said uron is about 3.5 to about 12 percent, and said member about 5 to about 25 percent.
 10. The method of claim 1 in which said impregnated fabric is cured at a temperature of about 290* to about 350* F. for about 1/4 to about 30 minutes.
 11. The method of claim 5 in which said textile fabric contains synthetic fibers.
 12. A permanently creased garment as produced by the method of claim
 8. 13. The method of claim 8 in which said impregnated fabric is cured at a temperature of about 290* to about 350* F. for about 1/4 to about 30 minutes. 